Comparison of Efficacy of Pembrolizumab between Epstein-Barr Virus‒Positive and ‒Negative Relapsed or Refractory Non-Hodgkin Lymphomas / Journal of the Korean Cancer Association, 대한암학회지
We analyzed the outcome of 30 relapsed or refractory NHL patients treated with pembrolizumab, and compared the outcome between Epstein-Barr virus (EBV)‒positive and negative subtypes because EBV infection of tumorcells can upregulate PDL1 expression.
RESULTS:
Seven patients with EBV-positive NHL showed a response including NK/T-cell lymphoma (6/14, 44%) and primary mediastinal B-cell lymphoma (1/4, 25%) whereas EBV-negative subtypes did not respond such as diffuse large B-cell lymphoma and T-lymphoblastic lymphoma. We also evaluated PDL1 expression using tumortissue of 76 patients. High PDL1 expression (positive staining of > 50% of tumorcells) was more frequent in NK/T-cell lymphoma and primary mediastinal B-cell lymphoma than other subtypes. Thus, PDL1 expression was significantly higher in EBV-positive (18/32, 56%) than EBV-negative NHL (4/38, 11%, p < 0.001). Furthermore, NK/T-cell lymphomapatients with high PDL1 expression showed a higher response (4/6, 67%) than those with low PDL1 expression (1/5, 20%).
CONCLUSION:
Pembrolizumab could be useful as a salvage treatment for relapsed or refractory EBV-positive NHL, especially NK/T-cell lymphoma. However, its efficacy in EBV-negative NHL with low or absent PDL1 expression is still not clear although pembrolizumab could be a potential treatment option for relapsed or refractory NHL.